The invention described here is a cam cleat intended for locking sheets, halyards, other lines etc. primarily on boats and especially sailing boats.
Known cam cleats are mainly designed in accordance with one of the two principles explained below.
The cam cleat has generally one fixed and one moving part. In one design the moving part is pivoted near its end, this end being situated closest to the point of entry of the line. The intention is that the strain is taken on the line after which the moving part is pressed against the line, overcoming the force of a spring which otherwise pulls the moving part away from the line, the line is then released with the result that it is wedged fast by the serrated edge of the parts mentioned. Thus this cam cleat does not secure the line if an unexpected jerk occurs in the line while it is being pulled home and the line may be pulled out of the hands of the person pulling. It can be seen that this securing process requires a free hand. Furthermore, to release the line it is necessary to pull harder on the line than the actual load on the line in order that the moving part shall be released and return to its rest position under the action of the spring mentioned above.
In another design the moving part is pivoted as above but a spring presses the moving part against the fixed part. The cam cleat therefore secures the line if an unexpected jerk occurs as described. To release the line the moving part is controlled by means of a lever. Since the moving part is pivoted at the incoming end of the line, when the line is released the serrations of the moving part are forced along the line in such a way that the line is further tensioned until the opening between the parts mentioned is sufficient to allow the line pass. This sometimes makes it difficult to release the line when it is under great strain.